Types of Relays - Normally Closed, Normally Open, Double Throw Type Relay

Relay and Fuse

Types of relays
Relays are classified into the following types, depending on how they open or close:

1. Normally open type relay:

This type normally opens, and closes only when the coil is energized.

(A) and (B) in the diagram

2. Normally closed type relay:

This type normally closes, and opens only when the coil is energized.

(C) in the diagram

3. Double throw type relay:

This type switches between two contacts, depending on the state of the coil.

(D) in the diagram